Gas mask



0st. 26, 11943. NATHANSON 2,332,662

GAS MASK Filed Sept. 21, 1942 MVENTOR AXNATHANSON Patented Oct. 26, 1943 UNITED isTATEs rATfENT :G FFJ CE V GASMASK lvlaxiNathanson, Montreal,Quebec,Canada I Application September 21, 1942, sunrise-45am:

1 Claim. (oi. 123-143) This invention has, for its principal object, the provision of improved anti-gas respirator apparatus which can be used with greater comfort and safety as compared with Conventional apparatus of this type.

The main feature of the invention consists in the provision of a head enclosing hood which is provided with air admission and discharge openings and which, when in use, is maintained filled with air under superatmospheric pressure by forcing air inwardly through said air admission opening at a rate in excess of the discharge capacity of the air discharge opening, the leakage of air through the last mentioned opening serving the dual purpose of preventing ntrance of gas therethrough and ensuring a sufficient circulation of air through the hood to maintain the head of the wearer in a relatively cool and comfortable condition.

Further features and advantages of the inven- Referring more particularly to'the drawing, 5

designates a head enclosing hood or mask provided with a closely fitting neck encircling portion 6, an air admission opening '1 and an air discharge opening 8, the latter being preferably located directly in front of the eyes of the wearer and being unobstructed. Sealing strips 9 and it ar secured to the inside of the hood or mask 5 at the upper and lower edges of the opening 8.

The strip 9 is arranged to engage the forehead of the wearer while the strip [0 is arranged to engage the nose and cheek bones.

An air supply tube H has one end connected to the hood or mask 5 at the opening I and the other end secured to a filter casing l2 containing a suitable gas absorbing substance l3. The top wall of casing I2 is provided with air outlet openings [4 placing said casing in communication with air supply tube H while the bottom wall of said casing is provided with air inlet openings l5 placing said casing in communication with a fan housing l6 containing a fan I! which is driven into the fan housing l6 by the motor driven fan I1 and is forced into the hood 5 through the filter casing l2, air supply tube H, and hood opening I. he rat at which the air is thus supplied to the hood 5 through the air admission opening 1 is greatly in excess of the rate at which air is discharged from the hood throughthe leakage opening 8. This ensures that the hood 5, when in use, will always be maintained filled with air at superatmospheric pressure and also provides for a circulation of cooling air through the hood from the air admission opening to the discharge opening 8. At the latter opening the air escapes at sufiicient volume and velocity to prevent any possibility of gas leaking inwardly through said opening. It may also be noted here that, owing to the provision of the sealing strips 9 and ID, the air passing to the discharge opening 8 is caused to flow horizontally between the sealing strips and across the eyes of the wearer before being discharged through the opening 8. This obviates any possibility of gas leaking inwardly through the opening 8 and coming in contact with the eyes of the wearer of the hood.

It will be understood that the specific embodiment of the invention illustrated in the present drawing is cited merely by way of example and that the principles of the invention may be embodied in any type of anti-gas respirator apparatus. The main feature of th invention consists in maintaining the head enclosing hood filled with filtered air under superatmospheric pressure while making provision for sufiicient leakage of air from the hood to keep the head of the wearer in a relatively cool and comfortable condition and, at the same time, to prevent inward flow of air through the leakage opening of the hood.

The fan driving motor 58 is provided with leads i8a which may be connected to a battery or, if desired, may be fitted with a plug adapted to be inserted in a suitable socket.

The apparatus described herein is especially adapted for the use of the driver and other occupants of an armored tank since, in this case, the

motor [8 may conveniently be connected to a battery or socket arranged inside the tank. The apparatus may, however, be used in other confined spaces where the user is forced to endure conditions of excessive temperature or poor ventilating conditions for a considerable period of time. If the apparatus is intended to be used as a portable self-contained apparatus, th motor 18 may be connected to a small battery which is carried about the person of the user.

Having thus described what I now conceive to be the preferred embodiment of the invention it will be understood that various modifications may be restored to within the scope and spirit of the appended claim.

Having thus described my invention, what I claim is:

Respirator apparatus comprising a head and face covering hood provided with a neck portion adapted to closely encircle the neck of the wearer, the face covering portion of the hood being provided with an air admission opening and an air discharge opening, the air admission opening being located below the nose of the wearer and the air discharge opening consisting of a single relatively long and narrow unobstructed slot extend ing across the hood in front of theupper portion of the nose and both eyes of the wearer, upper and lower sealing strips xtending respectively along the upper and lower edges of said discharge opening and projecting inwardly therefrom into engagement with the face of the wearer, said strips forming the upper and lowerwalls of a horizontal air passage which is open at both ends to the interior of the main portion of the hood, means for forcing air under pressure into the hood through said air admission opening at a rate in excess of the'air dischargevcapacity of said air discharge opening whereby said hood is maintained filled with air under suepratmospheric pressure, the air thus supplied to the main portion of the hood being caused to flow horizontally between the sealing strips and across the eyes ofthe wearer before being discharged through the discharge opening. v 1

- MAY NATI'IANSON. 

